The present invention relates to a heat treatment apparatus and a substrate processing system incorporated in a resist coating/developing system for heating or cooling a substrate such as a semiconductor wafer or an LCD (liquid crystal display) substrate.
In a photolithography process for manufacturing a semiconductor device, a photoresist is coated on the substrate and the resist-coated film is exposed to light and developed. The series of processes is carried out in the resist coating/developing system constituted of heating units such as a prebake unit and a post bake unit. Each of these heating units has a hot plate having a built-in heater of a resistance heating type. In the peripheral portion of the hot plate, a plurality of small projections are provided. The substrate is supported by these small projections, so that a small space is created between the substrate and the hot plate. The substrate is heated by receipt of heat radiation (heat energy beams) emitted from the hot plate.
At this time, air around the hot plate is heated and raised in temperature. The hot air thus heated rises up within a chamber and exhausted through an exhaust port formed through-an upper cover. The hot air comes into an ascending air stream which flows from the outer peripheral portion of the hot plate toward the center and is converged and exhausted from a position right above the substrate. As a result, part of particles contained in the air may fall down on the substrate, causing a problem of particle adhesion.
In addition a conical-form recess is formed around the exhaust port in the lower surface portion of the cover. The hot air is guided along the conical-form recess, formed into a spiral air stream and flows toward the exhaust port. However, the flow of the hot air tends to stagnate near right below the exhaust port. The stagnant hot air has a thermal influence upon the wafer W, rendering temperature of the wafer W non-uniform.
Furthermore, the height from the floor to the ceiling of the clean room is limited to a certain range. Therefore, it is necessary to reduce the height of the apparatus. However, a conventionally-used heat treatment apparatus has the upper cover, so that the height of the apparatus is large.
An object of the present invention is to:provide a small heat treatment apparatus capable of heating a substrate uniformly while preventing particles from being attached to the substrate.
The heat treatment apparatus according to the present invention comprises:
a chamber;
a hot plate for supporting and heating a substrate in a chamber;
a gas supply mechanism having a single or a plurality of gas blow-out ports and arranged in an upper space above the hot plate in the chamber, for supplying a gas along the substrate so as to cover the substrate placed on the hot plate; and
an exhaust mechanism having a single or a plurality of gas convergent exhaust ports which face the gas blow-out ports with the hot plate interposed therebetween, for converging and exhausting the gas blown out from the single or the plurality of the gas blow-out ports, from the chamber, the single or the plurality of the gas convergent exhaust ports having an effective exhaustion opening length L2 which is shorter than an effective blow-out opening length L1.
The heat treatment apparatus further comprises a control section for controlling the gas supply mechanism and the exhaust mechanism to form gaseous streams which flow in substantially parallel to an upper surface of the substrate from the single or the plurality of the gas blow-out ports to the single or the plurality of the gas convergent exhaust ports, in the upper space above the substrate.
The exhaust mechanism has two convergent exhaust ports arranged at a distance, and further comprising a switching mechanism for switching exhaust operation between the two convergent exhaust ports.
The gas blow-out ports consist of a plurality of holes arranged lengthwise along a linear pipe which is at least longer than a diameter of the substrate, and
the convergent exhaust ports consists of at least three convergent exhaust holes arranged so as to face the linear pipe at an equal distance from the linear pipe;
The heating treatment apparatus further comprises switching means for switching the exhaust operation between the at least three exhaust holes.
Furthermore, the heat treatment apparatus comprises an open/shut mechanism for opening and shutting the convergent exhaust holes individually.
The control section selects some holes from the convergent exhaust holes and instructs the open/shut mechanism to open the convergent exhaust holes selected.
The heat treatment apparatus further comprises a parallel moving mechanism for moving the convergent exhaust holes in parallel with the linear pipe.
The control section controls operation of the switching mechanism to gradually switch gaseous-steam directions from the gas blow-out ports toward the convergent exhaust holes.
The heat treatment apparatus further comprises exhaust port moving means for moving the convergent exhaust ports along the gas blow-out ports so as to continuously switch the gaseous-stream directions from the gas blow-out ports toward the convergent exhaust ports.
The chamber has upper and lower surfaces substantially closed and a lateral surface having an opening formed therein for loading/unloading the substrate.
The heat treatment apparatus according to the present invention comprises:
a chamber;
a hot plate for supporting and heating a substrate in the chamber;
a first pipe having a single or a plurality of gas blow-out ports for supplying a gas along the substrate so as to cover the substrate placed on the hot plate in an upper space above the hot plate in the chamber;
first and second exhaust ports facing both ends of the first pipe with the hot plate interposed therebetween;
a second pipe interposed between the first and second exhaust ports;
a third and fourth exhaust ports facing both ends of the second pipe with the hot plate interposed therebetween, the first pipe being arranged between the third and fourth exhaust pipes;
a gas supply system communicating with the first and second pipes for supplying a gas to each of the first and second pipes;
an exhaust system communicating with the first, second, third, and fourth exhaust ports, for exhausting the gas through each of the exhaust ports;
a first switching unit for selectively switching the communication between one of the first and second pipes and the gas supply system;
a second switching unit for selectively switching the communication between either a pair of the first and second exhaust ports or a pair of the third and fourth exhaust ports, and the exhaust system; and
a control section connected to the first and second switching units, for alternately switching a first connection state for flowing the gas from the first pipe to the first exhaust port with a second connection state for flowing the gas from the first pipe to the second exhaust port, and for alternately switching a third connection state for flowing the gas from the second pipe to the third exhaust port with a fourth connection state for flowing the gas from the second pipe to the fourth exhaust port, as well as for alternately switching a first and second connection state with the second switching means.
The heat treatment apparatus according to the present invention comprises:
a chamber;
a hot plate for supporting and heating a substrate in the chamber;
gaseous stream formation means for supplying a gas along the substrate so as to cover the substrate placed on the hot plate and for exhausting the gas, thereby forming a gas flowing region in a triangle or trapezoid form in an upper space above the hot plate in the chamber, in a plan view; and
gaseous stream switching means for switching a directions of gaseous streams formed by the gaseous stream formation means.
The gaseous stream formation means comprises three porous pipes for blowing out the gas in successive different directions which differ by an angle of 120xc2x0;
means for switching supply of the gas to the three porous pipes; and
exhaust ports each facing the corresponding porous pipe with the hot plate interposed therebetween.
In this case, each of the three porous pipes is formed straight and arranged in the triangular form so as to surround the hot plate; and
the exhaust ports are located respectively at three apexes of the triangle formed of the porous pipes.
Furthermore, in this case, three porous pipes each having an arc shape and arranged in a ring form so as to surround the hot plate in a plan view; and
the exhaust ports are positioned at three joints between the porous pipes.
The gaseous stream formation means has four porous pipes for blowing out the gas in successive directions which differ by an angle of 90xc2x0, means for switching gas supply to the four porous pipes, and exhaust ports each facing the corresponding porous pipe with the hot plate interposed therebetween.
The four porous pipes each being formed straight and arranged in a square form so as to surround the hot plate, in a plan view, and
the exhaust ports are positioned respectively at four apexes of the square formed of the porous pipes.
The four porous pipes each having an arc shape and arranged in a ring form so as to surround the hot plate, in a plan view, and
the exhaust ports are positioned respectively at four joints of the ring formed of the porous pipes.
The gaseous stream formation means comprises
a circular rail concentrically arranged around the hot plate;
an arc form pipe moving on the circular rail for blowing out the gas inwardly to a center of the hot plate;
an exhaust port member moving on the circular rail, for exhausting the gas; and
moving means for synchronously moving the exhaust port member and the arc-shape pipes with the hot plate interposed therebetween.
The heat treatment apparatus according to the present invention comprises:
a chamber;
a hot plate for supporting and heating a substrate in the chamber;
an exhaust mechanism having a single or a plurality of exhaust ports for exhausting a gas in a direction substantially parallel to a main surface of the substrate placed on the hot plate;
a gas supply mechanism facing the exhaust ports with the hot plate interposed therebetween and having gas blow-out ports whose total length involved in blowing out of the gas is greater than that of the exhaust ports; and
an air board for guiding the gas blown out from the gas brow-out ports to the exhaust ports.
The air board consists of
a first board member extended from an end of an array of gas blow-out ports to an end of an array of the exhaust ports, and
a second board member extended from the other end of the array of the gas blow-out ports and the other end of the array of the exhaust ports.
Furthermore, the heat treatment apparatus of the present invention comprises:
a sensor for detecting temperature of the hot plate; and
control means for controlling at least one of the gas supply mechanism and the exhaust mechanism on the basis of the temperature detected by the sensor.
The substrate processing system according to the present invention comprises:
a chamber;
a hot plate for supporting and heating a substrate in the chamber;
an exhaust mechanism having a single or a plurality of exhaust ports for exhausting a gas substantially in parallel with a main surface of the substrate placed on the hot plate;
a gas supply mechanism facing the exhaust ports with the hot plate interposed therebetween and having a gas blow-out ports whose total length involved in blowing out of the gas is greater than that of the exhaust ports;
a housing having triangular-prism corner assemblies each having a triangular bottom surface whose apex corresponds to the exhaust port and whose bottom line corresponds to the gas blow-out ports, for surrounding the hot plate;
a plurality of heat treatment units symmetrically arranged in the housing;
a main arm mechanism surrounded by the heat treatment units, for transporting the substrate to each of the heat treatment units; and
control means for controlling the main arm mechanism and the heat treatment units, independently.
The heat treatment units consist of four units each being arranged at a corner of the chamber in a plan view.
The most inner part of each of the corner assemblies is formed with a right angle in a plan view and the exhaust port is arranged in the most inner part.
According to the present invention, air streams containing dust lost their speed in front of the exhaust ports, it is possible to prevent the dust from falling on the substrate to form particles. In addition, it is possible to prevent non-uniform heating of the substrate without causing stagnation of the air on the substrate. Furthermore, it is possible to reduce the height of the treatment apparatus.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.